Electrophoretic display technology is a display technology of paper-like display devices that develops early, and in which a colored charged ball is moved in a liquid environment by applying an external electric field so as to show display effect with different colors. Electrophoretic (or E-Paper) display technology has been widely used as it combines advantages of both plain paper and electronic display.
However, an existing electrophoretic display device generally has a low contrast ratio. Therefore, how to improve the contrast ratio of an electrophoretic display device has become a technical problem to be solved urgently at present.